r/PCB

This is my own custom Arduino board. It is 4 layers. I would like to receive your thoughts, recommendations, suggestions and comments.

Edit: Added Schematic as comment
Edit2: added an explanation of the different pots/switches underneath the schematic-comment here

https://www.reddit.com/r/diypedals/s/GP3GNY2MfV

Recently posted about this project already, but since I reworked the Layout and all traces and completly finished them, I thought posting new would be more usefull.

It's my attempt to a Tubescreamer-based guitar overdrive pedal and my very first own pcb-design ever. I would highly appreciate some input regarding the pcb so far and if there are obvious improvements possible or mistakes done.

Signal-Traces are 0,5mm/20mil and power-traces (V9+ and V4,5+) are 1mm/40mil. Tried to stick to minimal distance of 1mm/40mil, in some corners etc it's more like 0,6-0,7mm/23-24mil (but only short distance). On the lower left corner are 3 traces very close (0,2mm/8mil) to each other, but that is on purpose to reduce possible loop surface (I hope that is the correct term in english), since that footswitchable "driveboost" mod can tend to oscilate the op-amp in certain settings. I will actually use cables for a fair distance of that part of the signal instead of traces which I twist together for the same reason (twisting helped a lot on my prototype, which is a TS-Kit with cablewired mods)

Ground via gnd-poures on both sides and with the help of several vias. Via's are all 0,6mm holediameter and 1mm in total. I've also placed several GND-Pads on the PCB's just in case and for more flexibility when actually wiring it all together.

Most pads in the lower-middle part are actually 9V-connections for the switching of 2 bi-color LED's. The switch in the upright corner is also involved in switching the led's, but routing that 9v-connections of the switch through the whole board seemed......tricky, so I will actually use wires for that part aswell and have prepared pads for that.

Input/Output and DC Jacks will be wired offboard.
I hope that is all info needed for the more experienced and helpful people here in the sub :) So, roast me please! Did I do good, bad or at least ok'ish? Any obvious mistakes or easy ways for obvious/big improvement? As I said, it's my very first own pcb, so my experience (and knowledge) is fairly low. I really want to make sure that this is a decent board without mistakes before ordering :D

Hi everyone!

This is my first PCB, so I'm posting the schematic and PCB layout (4-layer) here to ask for a review. I'd really appreciate any feedback, especially if you spot mistakes or design choices that could be improved. I'm mainly interested in learning from the mistakes before I manufacture the board.

The PCB is a small battery-powered device for measuring force using a half-bridge strain gauge, while also acquiring motion data from an IMU.

Main components:

- ESP32-C6 = main MCU (Bluetooth communication)

- MCP3561 = ADC for acquiring the strain-gauge signal

- BMI270 = 6-DoF IMU for acceleration and gyroscope measurements

- TPS63020 = buck-boost converter generating 3.45V from a 1S LiPo battery

- LP5907 = LDO generating 3.3 V from the 3.45 V rail

- TPS3700 = battery undervoltage/discharge protection

The PCB has the following pogo-pin connections:

- 2 pins for battery charging

- 2 pins for measuring an external resistor value

- 4 pins for connecting the two strain gauges forming the half-bridge

Q1 and Q2 are intended to protect the battery from a short circuit if the pogo-pin contacts are accidentally shorted by a conductive/metallic surface.

Any criticism is welcome because this is my first PCB and I'm trying to learn as much as possible before sending it to manufacturing.

Thanks!

This is my first PCB build. Any comments will be helpful. Yes, I do know that there are a lot of vias.

It's an mp3 player using a pcm5102a, TRRS headphone jack, microSD reader, USB C, ESP32-S3-N16R8, female headers, tp4056, and a battery connector (picoblade). I'm using a SPDT slide switch as a SPST slide switch (couldnt find any SPST ones, so I had to make do).

I'm routing VBAT through the switch and routing out vbat_clean out of it, but for the TP4056 module, i connect the BAT pin to VBAT and NOT vbat_clean, is this okay? (primary question)

Please let me know if there's anything wrong or if I should change anything because It's my first ever schematic and I pretty much have no idea what I'm doing haha.

This is the 2 pcb for my line follower robot, I plan on plugging in a 3s lipo battery into the xt30 to power the board, then just connect the two pcbs via ffc.

I'm not sure how I'm going to model the chasis, I wanna just have it 3d printed but I don't know any applications to use so the dimensions would be accurate to the pcb.

I'm pretty new to pcb making so there's probably some problems with the tracing.

another thing, I have no clue if I have the ffc latch backwards or not so there's that.

Please tell me I did things right this time lol

The flash and USB port are separate from the board

A friend of mine sent me this diagram and asked if I can make it. I told him I can and then he asked me to make a couple dozen. I’d really like to use a printed board for it, but I have no idea how to design one. Is there some sort of crash course I can take?

I made a PWM fan hub/controller for my passive cooling gpu. Support DS18B20, NTC, manual as temperature source, Curve-based controller, scheduling,... Temporarily closed-source for development, open-source soon.

For PWM, I'm using an NPN open-collector driver, combined with a tachometer level-shifter/divider which I found from here

And definitely got a tear in my eye when the debugger was able to communicate with the mcu 🥳

How does it look? There are these weird looking white dots in the middle of the pads, is that normal?

Is this circuit too corroded or are the two cylindrical things batteries that need replaced. Apologies I’m uneducated on any circuits and electronics.